Quantitative and morphological changes in neurons and neuroglia in the indusium griseum of aging mice.

The indusium griseum was investigated quantitatively in 5-mo-old and 18-mo-old mice. There was no difference in the number of neurons between 5 and 18 mo, but the number of neuroglia increased by almost 30%. Astrocytes and microglia increased in number, but oligodendrocyte number remained unchanged. There was no significant variation in the volume density of neuronal perikaryon, neuropil, or blood vessels with age.